Mezzion Pharmaceuticals Celebrates Major Enrollment Achievement in Fontan Clinical Research

Mezzion Pharmaceuticals Achieves Major Enrollment Milestone in FUEL-2 Trial

Mezzion Pharmaceuticals, Inc., headquartered in New Jersey, announced a critical update regarding its Phase 3 clinical trial, FUEL-2, which is the largest of its kind ever conducted for adolescents and young adults with Fontan circulation. The trial has successfully randomized about 50% of its targeted 400+ participants, a milestone that brings renewed hope to a community that has faced significant challenges due to complex health issues.

The Fontan procedure is a surgical intervention that is necessary for children born with single ventricle congenital heart disease. While survival rates have improved due to advanced medical care, patients in this community remain at high risk of heart failure and other serious complications. Unfortunately, there are currently no FDA-approved pharmacologic therapies available for these patients, making the significance of Mezzion's trial even greater.

Dr. Rahul Rathod, the Global Principal Investigator for FUEL-2 and Director of the Single Ventricle Program at Boston Children's Hospital, emphasized the complexity of the Fontan journey. He stated, "The Fontan journey is long, complex, and often isolating. FUEL-2 aims to do more than advance treatments; it seeks to build hope, community, and scientific clarity around a disease that has gone too long without answers."

The investigational drug being evaluated in the FUEL-2 study is JURVIGO® (udenafil), a selective and long-acting PDE5 inhibitor that has shown positive clinical outcomes in prior studies for this population, particularly among those with reduced functional capacity. The original FUEL trial revealed substantial benefits for patients in this subgroup, making the findings not only clinically relevant but also impactful for daily living activities. The focus of the current FUEL-2 trial is on ensuring that the uptake of udenafil is measured accurately, especially as patients face increased risks of mortality associated with declines in their peak VO₂ levels.

The primary objective for FUEL-2 is to assess the changes in peak VO₂ following 26 weeks of treatment with udenafil. Declines in this measurement can predict significantly increased risks of mortality and hospitalization in Fontan patients. Dong Hyun 'Dean' Park, Chairman and CEO of Mezzion, shared his enthusiasm for the trial, stating, "Every child and young adult living with Fontan circulation deserves a future with better options. FUEL-2 reflects our deep commitment to science as well as to the families, clinicians, and advocates who made this vision come to life."

To maintain the highest standards of data quality, cardiopulmonary exercise testing (CPET) results from the trial will be centrally reviewed by The Lundquist Institute, ensuring consistency and precision across all sites involved. The trial is being conducted at over 30 leading children's hospitals in the United States and South Korea, underlining the extensive collaboration required to improve outcomes for the Fontan community.

Patients and families eager to learn more about the trial or to potentially enroll are encouraged to visit www.FUEL2Study.com or consult their healthcare providers at participating centers. The urgency is palpable as the trial gathers momentum in the second half of enrollment, aiming to pioneer the first FDA-approved therapy for this resilient population.

About Mezzion Pharmaceuticals

Mezzion Pharmaceuticals, Inc. is dedicated to developing transformative therapies for patients with rare and underserved conditions. As a late-stage biopharmaceutical company, Mezzion is not only invested in its investigational product JURVIGO® but is also committed to advocating for the needs of children facing severe health challenges. The company has received Rare Pediatric Disease Designation from the FDA and plans to submit a New Drug Application following the completion of the FUEL-2 trial.

For further information about Mezzion and its clinical trials, visit www.mezzion.com and www.FUEL2Study.com.

Please Note: JURVIGO® (udenafil) is still under investigation and has not been FDA-approved for these patients. The safety and efficacy have not been fully established.